Just got a fresnel lens for my 11x14. All 4 sides need to be cut down to size by around a half inch to fit the cameras back.
Anyone have and experience or suggestions on how to cut a plastic fresnel lens?
thanks
Just got a fresnel lens for my 11x14. All 4 sides need to be cut down to size by around a half inch to fit the cameras back.
Anyone have and experience or suggestions on how to cut a plastic fresnel lens?
thanks
Straight edge and new utility knife blade. You can score both sides to keep it from chipping and sand the edges after snapping the excess off.
Otherwise, a band saw with a fence will work too.
Or get a plastics knife from the hardware store + straight edge and cut like Vinny said, and snap off excess...
Steve K
Just curious which one you bought. I am also tempted to try one.
The eBay 'Deardorff' Fresnel now selling is not described well.
Currently I use a thin flexible $2 book reading plastic Fresnel I place on my DIY 11x14 GG.
Tin Can
My luck with a flexible lens for reading on an 8x10 was as good as with a high priced fresnel for one of the 4x5's.
Fresnel lens that I bought was marked for use on an 11x14 Deardorff and measures 11x14 inches with corners cut off. I'd assume that it was made to fit in front of the GG and having to shim both so that accurate focus is to be had. I have a 4x5 that has the same configuration with its GG shimmed to account for the Fresnel mounted in front of it. To use it on my 11x14 Chamonix, I have to cut it down to 10 9/16" x 13 9/16" to be able to mount it in back of the GG.
I have an older 8x10 Sinar Norma which I (crudely) adapted a book reading plastic Fresnel to many years ago. Little while back was able to obtain an OEM Sinar Fresnel lens with correct 4 mounting clips. To be honest, comparing the book reading Fresnel to the OEM Sinar Fresnel.... didn't really see any difference to the naked eye. When I used a magnifying loupe there is a difference (OEM Sinar a finer lensed fresnel), but both are 100% useable.
Greg Putting the fresnel in front of the gg is a relatively unusual position for it. There are exceptions, the most common of which is the Kodak fresnel on Crown and Speed Graphics. I'd certainly try putting it behind the gg, with the ridges pointing forward, and checking to see if it indexes properly.
Went to our local ACE hardware store and found a Plexiglass hand cutter. It cuts a "V" shape into the plexiglass. Was told not to use a utility knife blade because it only separates the material and distorts the edges. "You want to remove the material in the "V" cut to obtain a clean break." So clamped down a metal ruler and made about 12 passed with the cutter holding it at an angle so the one edge of the "V" cut at a right angle to the fresnel lens that I wanted to use. Simple bend of the plexiglass and it breaks exactly on the scored mark. Oh yes, scored the smooth side of the fresnel lens. Fresnel lens was a generic fresnel lens that I bought online. Placed it on the back of my Whole Plate camera's GG and it worked terribly. Pretty sure my fresnel was the just the wrong focal length. My 4x5 and 8x10 Sinar Normas have OEM Sinar brand fresnel lenses on them and they work excellently. I do have a slight recollection of one manufacturer offering 2 fresnel lenses for their cameras... one for use with wide angle lenses and the other for use with normal and tele lenses. Think it was the Linhof brand... maybe Bob could correct me or confirm me on this.
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